Shuster T A, Nagy A K, Conly D C, Farber D B
Department of Anatomy and Physiology, California State University, Long Beach 90840.
Biochem J. 1992 Feb 15;282 ( Pt 1)(Pt 1):123-8. doi: 10.1042/bj2820123.
Using the radionuclide 65Zn, we have demonstrated the direct binding of zinc to purified rhodopsin. 65Zn is eluted with detergent-solubilized rhodopsin from concanavalin A columns and remains bound to the visual pigment through a subsequent gel-filtration step. Zinc binding to purified disc membranes is highly specific and, of the ions tested, copper is the best competitor. Equilibrium-dialysis experiments indicate that zinc binding to detergent-solubilized forms of rhodopsin may increase on bleaching the photopigment. These results may have important implications for studies that indicate that zinc plays a role in retinal degeneration and normal photoreceptor physiology.
利用放射性核素65Zn，我们已证明锌能直接与纯化的视紫红质结合。65Zn与去污剂溶解的视紫红质一起从伴刀豆球蛋白A柱上洗脱下来，并在随后的凝胶过滤步骤中仍与视觉色素结合。锌与纯化的盘状膜的结合具有高度特异性，在所测试的离子中，铜是最佳竞争者。平衡透析实验表明，视色素漂白后，锌与去污剂溶解形式的视紫红质的结合可能会增加。这些结果可能对表明锌在视网膜变性和正常光感受器生理学中起作用的研究具有重要意义。
